Dental operating lamp



Feb. 6, 1951 Filed Oct. 22, 1946 DENTAL OPERATING LAMP E. HJGREPPIN 3 Sheets-Sheet l Feb. 6, 1951 E. H. GREPPIN 2,540,577 v DENTAL OPERATING LAMP 3 Sheets-Sheet 2 Filed ,0612. 22, 1946 Feb. 6, 1951 E, H GREPPIN 2,540,577

DENTAL OPERATING LAMP af fzaz Filed Oct. 22, 1946 3 Sheets-Sheet 5 n D 77 65 waff 1153.

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is, in general, a similar prolate spheroid, but superimposed upon the theoretical spheroid surface are convex flutes 43 arranged vertically as seen in Figs. 1 and 4. The unit 4| is made preferably of borosilicate glass containing ferrous oxide or ferrous oxalate, and cobalt, and either zinc or cadmium or a mixture thereof, so that it is both heat absorbing and heat resisting and color correcting. The details of the shape or configuration of the catadioptric unit 4|, and the composition thereof, and the optical results or effects produced thereby, are fully set forth in Patent No. 2,437,516, and need not be repeated here, reference being hereby made to said patent for a full disclosure thereof. The optical unit 4| in the present structure is preferably identical with the unit disclosed in said patent, except that in the present construction the top and bottom flanges designated in said patent by the numeral 3| are omitted, but this does not in any way alter the optical properties of the device, since said flanges in the disclosure of the patent were merely for strengthening purposes and had no optical effect.

As explained in said patent, the catadioptric unit 4| has curved lateral ends and an approximately straight top and bottom which lie in hori- )zontal planes when the optical axis of the unit is arranged horizontally. This is well seen in the present drawing, particularly in Figs. 1, 4, and 6. The casing has its rear face shaped to conform very closely to the rear face of the catadioptric unit, but throughout the major part of the area there is a slight space between the casing and the rear face of the unit, as seen in Figs. 4 and 6,

in order to avoid any possibility of scratching the reecting surface of the optical unit by contact with the casing. The unit is supported from the casing at four spaced points by pads 45 (Figs. 1, 5, 6, and 7) of soft material such as felt, cemented or glued to the inner or forward face of the rear wall of the casing It is held tightly and immovably against these pads by a curved molding strip 41 extending along the curve of the top edge of the optical unit 4| and having an angular cross section to embrace the edge as shown, and a similar molding strip 49 extending along the bottom edge of the unit, as seen in Figs. 5 and 6. The ends of both molding strips underlie and are held in place by lateral strips 5| at the ends of the casing, which strips 5| press rearwardly against soft pads 53 of felt or the like interposed between the strips 5| and the front faces of the lateral edges of the optical unit 4|. These strips 5| are secured to the casing by screws 55 or other suitable fastenings.

. A shelf or flange 6|, preferably formed integrally with the rear wall of the casing I, projects horizontally forwardly at the bottom of the optical unit 4I, throughout most of the width of the unit, as seen in Figs. l, 4, and 5. For a short distance at the center, however, this flange 6| is omitted, and is replaced by an integral flange 63 (Fig. 6) which is thicker and stronger and at a lower elevation than the flange 6| and which carries an insulating plate 65 which supports a lamp socket B1 held by screws 69. In the lamp socket is an incandescent lamp bulb 1| having a short illament 13 located on the optical axis of the optical unit 4| and substantially at one focus of this optical unit, as explained in said Patent No. 2,437,516. The lamp is fed with current through electric wires 15 controlled by a small toggle switch 11 mounted in an opening in the flange 63 as seen in Fig. 6, the switch being operated by a 4 handle 19 conveniently accessible at the bottom of the casing. Above the flange 63 and switch 11 is a plate 8| at the same level as the flanges 6| and forming in effect a smooth continuation of these flanges, bridging the space between them (around the lamp socket 61) in the central portion of the casing. A depending ange 83v at the front edge of the plate 3| abuts against the front edge of the flange B3, and the plate is held in place by screws 85 passing through this front flange B3.

At the top of the casing is a forwardly extending flange 9| preferably formed integrally with the rear wall |I and having a somewhat curved front edge as seen in Fig. 2. At the center, this top wall is somewhat raised and thickened as at 93 (Fig. 6) and forms a mounting for a hinge having a stationary leaf 95 secured to the underside of the flange 93 by screws 91. Pivoted to the stationary leaf 95 by the usual pintle is the movable hinge leaf having a radial part |0| supporting an arcuate part |03 concentric with the pintle, and extending through a central angle of about at the end of which arcuate part is a radial part |05 secured by screws |01 to the top ilange portion |09 of a swinging door having also a front plate and a curved bottom plate ||3 curved downwardly and rearwardly and abutting against a shoulder on the bottom flange E3 when the parts are in the closed position shown in Figs.5 and 6. The` door parts |09, and ||3 are preferably made integrally from a single piece of opaque material such as metal or molded opaque plastic. A resilient spring clip I5 is secured by the screw ||1 to the innerface of the front wall near the bottom thereof and resiliently engages a protuberance on a member I9 mounted on the flange 83, thus constituting a latch resiliently holding the door in closed position. By pulling outwardly or forwardly on the lower part of the door with sufficient force to cause the resilient latch I5 to dlsengage itself from the member H9, the entire door may be swung forwardly and upwardly about the hinge 95, IUI as a pivot, from the position shown in full lines in Fig. 5to the position shown in dotted lines. In its uppermost position shown in dotted lines the radial portion |0| of the hinge comes into contact with the forward edge of the flange 93 of the casing which projects forwardly beyond the hinge pintle as seen in Fig. 6, and prevents further rotary movement of the hinge, stopping the parts in a position such that the upper rear edge of the part |09 of the door does not quite touch the top of the casing 93 and thus does not mar the casing or cause any damage to the parts. Y l

In the upper part `of the door is an opening of substantial size as seen in Figs. l and 6, which opening is lled with a plate |2| of translucent material, preferably a translucent plastic having light-transmitting and diffusing properties approximately similar to those of ground glass. This member |2| is conveniently curved through a substantial arc when viewed in vertical section as in Fig. 6, and somewhat curved on a larger radius in horizontal section to agree with the larger radius horizontal curvature of the front face of the door as seen in Fig. 4. Along the bottom of the window opening in which the translucent member |2| is placed there is a straight flange or rib |23, on the front edge of which there is a horizontally elongated metal strip |25 constituting a resilient spring clip held by screws |21. The material of the rib |23 is slightly relieved or recessed behind the upper part of the f 11H5, and the: upper edge 'of the strip; fis; slightly curyediiorwardlygjto assisteasyzinseriiipnf` ofratransparency behind Lthe strip. l'Any transparencywhich is helpful. to.` the dentist, suchcor example `as .an 'X-.ray lm showing. athe teeth which are to .be worked upon, .may be 'held :in place asshownlat :|29 .in 'Eigg. 6;;by thrusting its loweredge -.downwardly between the :springfin'ln |5251 and the flange |23, andwhen'thus :held by; the spring clip .the:.transparency Willmaintainfan upright position. .as .indicated in. Eig..6r.and will he illuminated l,by diftused light :coming from the lampy 1|. .and passing' .th-rough the translucent window A|.-2.|.

Lower down on the front face of the-i'ron'twall offztlxedoor` |i|`=|- is--a secondjhorizontally:extending rib-131| Ehai/ling an elongated metallic-'spring -clip ||3lmounted against Athe front .faceoff thefribbyv screws |35. ThisSpringcIip |33fn'ray-:be-:used'fforr mounting any diagram, chart, :orindicia 1F31:

whichw will be helpful to Ithe dentist while he 'isy being :a polished metal reflector in -the shape of aragment'of -asphere, mounted :in such positionas to be directly `in iront vvof y'the 'incandescent filament '13 of the-lamp bulb. The'upper partfof the reflector is cut oil4 or-*truncated as -at 4-IZlB so that -the reflector 'will lnot interfere'wi'th passage of light from the filament obliquely upwardlyto thetranslucent window' |21|for the ypurpose of illuminating the X-ra-y film mother-transparency |29. VMost of the light passing` forwardly fromv the filament 13 in -other directions is, however, intercepted by the reflector-and reected rearwardly onto the optical unit 4|-, where the light is both reiiectedrand refractedto form thehighly desirable projected beam -ofilight having a -wide horizontal `spread butv a narrow -or confinedvertical spread, for -the'purpose above mentionedand as more fully `described in said Patent No. 2,437,516. v

' Thefdoor H19; l-'| i fl i3 -also has rearwardly-extending laterallanges |49 which extend rearwardly far enough to cut voff all rays of light which, if not -c-ut ofi, would pass forwardly Ibeyond the 'front'edges-of the optical -un-it 131| at the ends thereof. Tt will be noted from Fig. 4 that the incandescent bulb 'H is set back Fa substantial distance behind theyertical plane oithefront; edges of the optical' unit ll''l, `and 'it Ywill lbe noted'` that the lside walls '|49 of the door extend back far enough to touchr or go `'slightly behind 'a straight line which maybe .drawnfrom the center of the bulb 7| to the extreme ends of the optical unit I orto the molding strips 54| atthe ends of the optical unit. Hence it is assured that any ray of light from the filament 'i3 'whichv passes behind the side iianges |59 oithe door will necessarily fall on Ithe optical unit andbe reflected .and refracted thereby, so -as lto `be optically directed and controlled in the-desired man-ner. No matter ffromwhat. position one looks'rat thisv dental lam-p,

there is no possibility of experiencing the :glare and disagreeable sensation which would be caused by 1a `direct View of" the incandescent .dla-ment. ln yany position ci observation', .illumination can.

be received; only b yflight rays which have ib'eeri reflectedcand retracted:byfthezopiticalnnit f The-ireectedizand. retracted rays comingro near the centerofv 'the :catadi'optric :unit llfare;

` ofcourse, obstructedzgand: fout oiif by fthe .door 'll 9,

|||, H3, |49, so that the rays which illuminate the foral Gay-ity A:necessarily fcom/efrom those.' portions -of the-'optical unit il; 'which lieto thel leftA and right :ofi fthe doonw'hen viewed Aas lin Fig. Thus fthe 'fi-leid :of illumination vis'Tii'glfit'edley 'rays converging towardfthe feld fromdilierentdire tionsV a'ta 'stibstantial'angle to each fother, which makes io-r well nigh shadowless illumination of# they @iie'ldg eliniinating-v l:or greatly 'reduc-ing `tl-ieshadows which Wouldbe 'cast -byA the dentis'ts able ior instant inspection by the dentist 'asthe work progresses, in addition to vwhich 'they also'in a'position wherethey can be 'easilyviewed b y the patient .himself if the 'dentist desiresto point out -or explain 'to the ,patient any o` .the features of the X-.ray or nfjth'e tooth chart.

Whenever it is 'desiredto lreplace the 'incandesr I cent bulb or to clean the reflector 'Efiljcr to, clean the front. aoeof the. optical unit ill.; the; door may be quickly and easily thrownA openjfrom@ the full line position of Fig. '5 '.to 'the olotteilline-Q position lin that ligure., thus obtaining instant, access tothe interior o the lamp. When the door isoloseolv again,y the spring 'latch '|115 operates automatically and holds it 'in closed .riosltionv It willlbe .noted-'that the .door constitutes what maybe Adescribed zaptly as abridge member, sin'e..

it bridges acrossthe narrow `dimension (.that,.1.S., theheight). of the optical unit lli|,.`in` adirect'lon' transverse to the major .dimension (thatV is 'the lateral width).-.of the unit, .and occupies aposition.` in vfront of` the source of lights'o as .to block o l directJ forward transmission of; light from the. source.

It is seen from the foregoing .disclosure that the :above-.mentioned Aobjects .of Athe .invention .are admirably fulfilled. Itis .to be understoodthat..

the foregoing .disclosure isgivenhy wayof .illus. c

tratve` example only, .ratherthan by way .of llimi,-

tation, vand that without. departing yfrom .the-` invention,` the details mayv be,- varied within thef scope "of thel appendedclaims. n

What is-claimed is:

.1. A dental` operating -lampincluding .a Lcas-,j-

ing containing-a reflecting'element having agem;V eral, rearwardly' convex rand forwardly concave sha-pagsaid element being substantially elongated in one.direction comparedfto its dimension transverse to the elongated direction, @a bridge mem-P.;`

b'er- Vmounted on said 7casing land lbridgingsaid -re-.v ectingvelement .in said transverse direction fat;

a point near the ,center- .of saidl element in the'.

direction of elongation fthereofyo-Souroeof light mounted behindsaid- @bridge member so 4that :light-.fl from .said source l.may 'pass :ojbliquely -rearwar tok saidreflecting element -andfthencegbe reilectedfforwardly past one sides'offsa-id bridge fmemben, saiclforfoftee.member beine. rof substantially opaque material and having a substantially translucent window portion, and retaining mea-ns adjacent an edge of said window portion for holding a dental transparency in position to be illuminated by light coming through said window portion.

2. A dental operating lamp including a casing containing a refiecting element having a general rearwardly convex and forwardly concave shape, said element being substantially elongated in one direction compared to its dimension transverse to the elongated direction, a bridge member mounted on said casing and bridging said'reflecting element in said transverse direction at a point near the center of said element in the direction of elongation thereof, a source of light mounted behind said bridge member so that light from said source may pass obliquely rearwardly to lsaid reflecting element and thence be reflected forwardly past one side of said bridge member, said bridge member being mainly of substantially opaque material and having a substantially translucent window portion, retaining means adjacent an edge of said window portion for holding a dental transparency in position to be illuminated by light coming through said window portion, and other holding means on said bridge member substantially spaced from said window portion for holding a tooth chart or the like in convenient position to be observed by a person in front of said lamp.

3. A dental operating lamp including a casing containing a reflecting element having a general rearwardly convex and forwardly concave shape, said element being substantially elongated in one direction compared to its dimension transverse to the elogated direction, `a bridge member mounted on said casing and bridging said reflect.- ing element in said transverse direction at a point near the center of said element in the direction of elongation thereof, and a source of light mounted behind said bridge member so that light from said source may pass obliquely rearwardly to said reflecting element and thence be reflected forwardly past one side of said bridge member, said bridge member being mainly of substantially opaque material and having a substantially translucent window portion, and spring clip means adjacent an edge of said window portion for retaining a dental transparency in position to be illuminated by light coming through said window portion.

4. A dental operating lamp including a casing, a source of light mounted in said casing, a rst reflecting element behind said source of light, said reflecting element being of relatively low height from top to bottom and being of relatively great lateral extent with the ends thereof curving forwardly to positions ahead of the transverse plane of said source of light and being of substantially continuous unbroken form throughout the entire width of said lateral extent, a bridge member extending from the upper central part of said casing downwardly in front of said source of light to the lower` central part of said casing, and a second reflecting element carried by the rearv face of said bridge member and located substantially directly in front of said source of light to reflect light rays therefrom rearwardly toward said first mentioned reflecting element.

5. A construction as described in claim 4, in which said first reflecting element has approximately the general shape of a portion of a prolate spheroid with said source of light approximatelyv at the near focus thereof.

`6. A dental -operating llamp including a casing substantially open at the front and having ap'- proximately parallel top and bottom walls and a rear wall curved to be generally concave on its front face and being of substantially greater lateral extent in a direction parallel tofsaid top and bottom Walls than its vertical extent in a direction between said top and bottom walls, a lamp socket mounted on said bottom wall near the center thereof, an incandescent electric lamp bulb mounted in and projecting upwardly from said lamp socket, and a bridge member movably connected to said upper wall approximately at the center thereof and extending therefrom down-- wardly in front of said bulb substantially to said bottom wall.

7. A dental operating lamp including a casing substantially open at the front and having approximately parallel top and bottom walls and a rear wall curved to be generally concave on its front face and being of substantially greater lateral extent in a direction parallel to said top and bottom walls than its vertical extent in a direction between said top and bottom walls, a lamp socket mounted on said bottom wall near the center thereof, an incandescent electric lamp bulb mounted in and projecting upwardly from said lamp socket, a bridge member movably connected to said upper wall approximately at the center thereof and extending therefrom downwardly in front of said bulb substantially to said bottom wall, said bridge member being mainly of opaque material and having a translucent portion, and

spring clip means for holding a dental trans parency in position in front of said translucent portion to be illuminated by light passing from said incandescent bulb through said translucent portion.

8. A dental operating lamp including a casing substantially open at the front and having approximately parallel top and bottom Walls and a rear wall curved to be generally conca-ve on its front face and being of substantially greater lateral extent in a direction parallel to said top and bottom wal-ls than its vertical extent in a direction between said top and bottom walls, a lamp socket mounted on said bottom wall near the center thereof, an incandescent 'electric lamp bulb mounted in and projecting upwardly from said lamp socket, a bridge member movably con-- nected to said upper wall approximately at the center thereof and extending therefrom downwardly in front of said bulb substantially to said. bottom wall, said bridge member being mainly of opaque material and having a translucent portion, spring clip means for holding a dental transparency in position in front of said trans.-A

lucent portion to be illuminated by light passing from said incandescent bulb through said translucent portion, and other spring clip means for holding a non-transparent dental chart or the like in position on .said bridge member vin front of an opaque portion thereof.

9. A dental operating lamp includingr a source of light, a catadioptric unit behind said source-L of light for directing and controlling light from said source so that the same will be projected in a beam toward the mouth of a dental patient,

two separate spring clip means for holding dental' indicia in front of said source of light, one of said spring clip means being in position to hold non-v transparent indicia such as a tooth chart or the like and the other being in position to hold transparent dental indicia such as an X-ray film or the like, and a substantially translucent member between said source of light and said transparentindicia so that said transparent indicia will be illuminated by diffused light from said source.

10. A dental operating lamp including a metallic casing, a glass catadioptric unit mounted in said casing, said casing and unit being relatively elongated in a lateral horizontal direction andv relatively constricted in a vertical direction, a source of light mounted in front of said cata- -dioptric unit to provide light to be reflected` and refracted thereby so as to be projected forwardly in a beam toward the mouth of a dental patient, and a handle projecting from each lateral end of said casing in convenient position to be grasped to adjust the position of said casing and the direction in which said beam of light is projected.

11. A dental operating lamp including a rearwardly convex and forwardly concave casing elongated in a lateral horizontal directionas compared with its vertical height, a forwardly,

concave reflector within said casing, said casing including a shelf projecting forwardly from a point near the center of the bottom edge of said reilector, a lamp socket mounted on said shelf, a tubular electric lamp engaging said socket and extending upwardly therefrom in a position forwardly of said reflector at its center, and a bridge member pivotally mounted on said casing for swinging movement on a hinge axis rearwardly of said electric lamp, said bridge member, when in normal closed position, extending in front of said electric lamp and obscuring direct forward passage of light rays therefrom.

12. A construction as described in claim 11, in which said reflector has a substantially continuous unbroken reecting surface inV said elongated direction from one lateral edge to the opposite lateral edge thereof.

13. A construction as described in claim 11, in which said bridge member has a major portion of opaque material and a minor portion of translucent material.

14. A construction as described in claim 11, further including a pair of trunnions on the rear convex face of said casing near the lateral ends thereof, means for mounting said casing on said trunnions for pivotal movement about an axis substantially parallel to the direction of lateral elongation of said casing and located approximately midway of the height of said casing, and a pair of handles projecting laterally from the lateral edges of said casing at points Ylaterally beyond said trunnions, in position to be grasped for convenient adjustment of said casing on said axis.

15. A construction as described in claim 11, in which a xed part of said casing projects forwardly beyond said hinge axis, and in which the pivotal mounting of said bridge member on said casing includes a hinge part extending from said hinge axis in a radial direction for a substantial distance and thence arcuately to said bridge member, the arcuately extending portion being spaced sufliciently far from said hinge axis to clear said xed part of said casing during opening and closing movements of said bridge member and the radially extending portion serving to contact with said xed part of said casingto limit the extent of swinging movement of said bridge member in an opening direction.

16. An illuminating unit including a rearwardly convex and forwardly concave casing elongated in a lateral horizontal direction as compared with its vertical height, a catadioptric unit within said casing, said catadioptric unit being of substantially transparent material and hav ing a convex rear reflecting surface lying closely adjacent the concave forward surface of said casing and having a generally concave forward surface provided with a series of integral flutes arranged approximately in planes perpendicular to the direction of lateral elongation of ,said casing, a flange projecting from the bottom of said casing forwardly past the bottom edge thereof near the midpoint of said bottom edge, a second iiange projecting from the top of said casing forwardly past the top edge thereof near the midpoint of said top edge, an electric lamp socket supported from one of said anges in position to hold a lamp approximately in front of the midpoint of said catadioptric unit, and a bridge member connected to one of said flanges and extending in a generally vertical direction to the other of said flanges and lying in front of a lamp held in said lamp socket to intercept direct forward rays from said lamp.

17. A construction as defined in claim 16, in which the lateral ends of said catadioptric unit extend farther forwardly than a lamp held in lamp socket, and in, which said bridge member has lateral flanges extending rearwardly at the sides of a lamp held in said lamp socket, far enough to intercept direct light rays from said lamp which would otherwise pass in front of said lateral ends of said catadioptric unit.

18. A construction as defined in claim 16, in whichthe front face of said catadioptric unit is freely open to the surrounding atmosphere for direct and unobstructed passage of light rays from said catadioptric unit forwardly to the place to be illuminated, except where intercepted by said bridge member.

19. A construction as defined in claim 16, in which said bridge member has a translucent portion of minor area, the major area of said bridge member being opaque.

20. A construction as dened in claim 19, further including a spring clip mounted on said bridge member adjacent an edge of said translucent portion, for holding indicia in a position alined with said translucent portion to be viewed by light transmitted through said translucent portion of said bridge member.

21. A construction as defined in claim 20, further including a second spring clip mounted on said bridge member at a point remote from said translucent portion, for holding other indicia in a position alined with an opaque portion of said .bridge member.

ERNEST H. GREPPIN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,393,027 Kirschberg Oct. 11, 1921 1,740,609 Lebby Dec. 24, 1929 1,917,292 Buchanan July 11, 1933 1,937,585 Luxmore Dec. 5, 1933 1,963,278 Pieper June 19, 1934 2,065,164 Wetzel Dec. 22, 1936 2,226,300 Alexander Dec. 24, 1940 2,297,781 Korengold Oct. 6, 1942 FOREIGN PATENTS l,Number Country Date 479,722 Great Britain Feb. 10, 1938 

